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How to use mysql JOIN without ON condition?
...ian product -- that is, every possible combination of 1 row from the first table and 1 row from the second. The cross join for a table with three rows ('a', 'b', and 'c') and a table with four rows (say 1, 2, 3, 4) would have 12 rows.
In practice, if you want to do a cross join, then use cross joi...
How to understand nil vs. empty vs. blank in Ruby
...
I made this useful table with all the cases:
blank?, present? are provided by Rails.
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Big-O summary for Java Collections Framework implementations? [closed]
...s next notes
HashSet O(1) O(1) O(h/n) h is the table capacity
LinkedHashSet O(1) O(1) O(1)
CopyOnWriteArraySet O(n) O(n) O(1)
EnumSet O(1) O(1) O(1)
TreeSet O(log n) O(log n) O(log n)
ConcurrentSkipListSet O...
How to vertically align into the center of the content of a div with defined width/height?
...I have found you have four options:
Version 1: Parent div with display as table-cell
If you do not mind using the display:table-cell on your parent div, you can use of the following options:
.area{
height: 100px;
width: 100px;
background: red;
margin:10px;
text-align: center;
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'console' is undefined error for Internet Explorer
...le.debug
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* Chrome 41.0.2272.118: debug,error,info,log,warn,dir,dirxml,table,trace,assert,count,markTimeline,profile,profileEnd,time,timeEnd,timeStamp,timeline,timelineEnd,group,groupCollapsed,groupEnd,clear
* Firefox 37.0.1: log,info,warn,error,exception,debug,table,trace,dir,group,groupCollap...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...doing this for a very finite set of values, then you could create a lookup table. Performing the indexing might be more expensive, but if you can fit the entire table in cache, then you can remove all branching from the code, which should speed things up.
For your data the lookup table would be 12...
access denied for load data infile in MySQL
...mple, this gives the permission problem:
LOAD DATA INFILE '{$file}' INTO TABLE {$table}
Add LOCAL to your statement and the permissions issue should go away. Like so:
LOAD DATA LOCAL INFILE '{$file}' INTO TABLE {$table}
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LIKE vs CONTAINS on SQL Server
...e an index, since it starts with a wildcard, so will always require a full table scan.
The CONTAINS query should be:
SELECT * FROM table WHERE CONTAINS(Column, 'test');
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Insert current date in datetime format mySQL
...re the current time just use MYSQL's functions.
mysql_query("INSERT INTO `table` (`dateposted`) VALUES (now())");
If you need to use PHP to do it, the format it Y-m-d H:i:s so try
$date = date('Y-m-d H:i:s');
mysql_query("INSERT INTO `table` (`dateposted`) VALUES ('$date')");
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Rails 4: List of available datatypes
... is not set to use :sql, then your schema.rb file wont be able to dump the table that uses types like :json. The schema will still be dumped for the tables that use default types but you'll see a comment for the table with special types like, "could not dump table...". Look here to set the schema_fo...